I've seen a severe lack of people understanding what slimes are, how farms work and other aspects. Here I'll explain everything about them.

This is a slime:

[ Register or Signin to view external links. ]

There's a good chance you've probably never seen one, these are rare mobs which only spawn below layer 16 (on version 1.6.6 and 1.7.3) and on a few specially selected chunks.

A chunk simply put is a 16x16 space that can reach as high as the sky and down to bedrock level.

The minecraft xbox map is around 1024x1024 blocks (1048576) if we divide that by the size of a chunk, 256 blocks, we get 4096 chunks in one map. Since only 10% of chunks can spawn slimes we multiply that by .10 and we get 409.6 (410) so only 410 chunks on the map can spawn slimes. The percentage of chunks that can spawn slimes is around 10.

This is the formula used to generate slime chunks, don't ask me how it works. I don't know.



Slimes require some type on opaque block underneath them to spawn. This means they won't spawn on things like torches, signs, glass, chests, fences, TNT, etc.

Large slimes need a 3x3x3 area to spawn, medium slimes need 3x3x2 and small slimes need 1x1x2 (1x1x1 is the block above them is not opaque)

Lighting does not affect slimes spawning yet they only spawn 1/10th as often as regular mobs. You should still light up the area around your farm just so other mobs don't spawn in that area.

Now when attempting to build a farm, DO NOT JUST START MAKING ONE. You have about a 10% chance of finding a slime chunk by just making a farm.

Now that minecraft has the coordinates on a map you should build on an actual chunk, whenever your X or Z coordinates are divisible by 16, you're standing on the edge of a chunk. An example would be if you're standing on X:80 Z:-48, the chunk extends from X:80-96 and Z:48-32 This is where you should build a farm if you're 100% sure slimes are able to spawn on the chunk.

Other people have been saying it has to be X blocks above bedrock. It does not. Slimes spawn anywhere below layer 16 on version 1.6.6 and 1.7. Bedrock is layer 5. This means they can spawn on bedrock level and 11 layers above it as well.

Many tools exist that can help you find slime spawning chunks. You simply input the seed your map used and set the boundaries you want it to search from. [ Register or Signin to view external links. ] and [ Register or Signin to view external links. ] are some of them.

These tools are used by inputting your seed which you get when you load the world and inputting your X and Z coordinates then choosing a distance. It will then highlight chunks in green which are able to spawn slimes and that is where you should build.

As of now, the only way to gather slimeballs is to kill slimes which are size 1. Apparently, slimes will not split into smaller ones if they are killed with a weapon except for a bow. This is the code to prove only size 1 slimes drop slimeballs.



Any questions can be posted below.